The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
In general, an environmentally friendly vehicle (a hybrid electric vehicle or an electric vehicle) may generate a driving torque by an electric motor (hereinafter referred to as “drive motor”) which gains a rotating force based on electrical energy. A hybrid electric vehicle among the environmentally friendly vehicles includes an electric motor in addition to an engine and a transmission such that the hybrid electric vehicle runs by the electric motor without driving the engine at low speed, and drives the engine with torque assistance of the electric motor when the vehicle speeds up.
The hybrid electric vehicles use the electric motor (it is called a ‘motor/generator’ in this art) having relatively better low-speed torque characteristics as a main power source at a low-speed and use the engine having relatively better high-speed torque characteristics as a main power source at a high-speed.
However, since the electric motor of the hybrid electric vehicle, different from a motor in general industry filed, shares a transmission housing with the transmission and the engine and is operated at a wide operation region, a length of the hybrid electric vehicle is longer than that of an engine-powered vehicle.
Meanwhile, the electric motor for vehicles is provided with a position sensor such as a resolver for detecting a rotation speed and a rotation position (rotation angle) of a rotor. The resolver used as the position sensor detects an absolute position of the rotor of the motor with an output signal of low AC voltage (about 0.5-5 Vrms).
The resolver includes a resolver stator and a resolver rotor. For example, the rotor of the resolver is mounted at a rotation shaft of the motor and the stator of the resolver is coupled to a cover of the transmission housing by a bolt in the hybrid electric vehicle.
According to conventional arts, a tab is formed at the cover in order to couple the stator of the resolver to the cover of the transmission housing by the bolt. That is, the stator of the resolver is mounted by engaging the bolt into the tab.
Since the resolver is coupled to the cover of the transmission housing by the bolt according to the conventional arts, the cover does not provide a space for mounting components of the transmission. For this reason, an additional housing space for disposing the components of the transmission is to be formed and thus a length of the transmission increases.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the present disclosure and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art.